选择频率 meaning in English
select frequency
selection frequency
Examples
- Preferred frequencies , frequency levels , and band numbers for acoustical measurements
声学测量的优先选择频率频率级和频带数 - By means of fourier integral for analysis of plus mag netic field frequency spectrum . it provides relation of magnetic field with maxim um frequency
利用付立叶积分对脉冲磁场进行频谱分析，讨论了脉冲磁场大小随所选择频率上限之间的关系 - A frequency selective surface ( fss ) is a metallic periodic structure with frequency selective properties . depending upon design , it may be low - pass , high - pass , band - pass , band - stop filter
频率选择表面( fss )是具有选择频率功能的一块金属周期结构，它可以被设计成低通、高通、带通、带阻滤波器。 - The equation including the nonlinear dispersion , i . e . the modified nonlinear schrodinger ( mnls ) equation , is a better model . in this thesis , we take mnls solitons as a model for femtosecond soltions . then based on the recently developed direct perturbation theory for perturbed mnls equation , we study the raman self - frequency shift of femtosecond solitons and its suppression by the means of frequency filters . for this purpose , first , we define the physical parameters of mnls solitons ; next , through the direct perturbation theory for perturbed mnls equation , under adiabatic approximation , we obtain the evolving parameters of mnls soliton on our questions and then choose the parameters of frequency filters based on it ; at last , we directly numerically simulated our questions by split - step fourier ( ssf ) method after improving the arithmetic of the differentiation of the nonlinear item for satisfying mnls equation
本论文以mnls孤子作为光纤飞秒孤子的模型，通过新近建立的mnls孤子直接微扰理论，研究光纤中由拉曼效应引起的飞秒孤子在传输中的自频移，以及通过频率滤波对自频移的抑制。为此，首先给出描述mnls孤子的各物理量，然后用mnls孤子直接微扰理论，解析地得到这些问题绝热近似下的孤子参数演化，并由此选择频率滤波的参数，最后用分步傅里叶方法，在对非线性项微商的算法做出了适合于mnls孤子的改善后，对拉曼效应及频率滤波进行了直接数值模拟，其中频率滤波参数用微扰理论确定。